The cyproconazole-type fungicides found in recent years have good fungicidal activity (cf. U.S. Pat. No. 4,849,439) and have an activity against human and animal dermatophytes and against phytopathogenic fungi.
Novel fungicidal agents based on cyproconazole and quaternary ammonium salts which have surprisingly powerful synergistic activities in the control and prevention of wood-destroying fungi have now been found.
The use of mixtures which entail synergistic effects has considerable economic but also ecological advantages.
Synergism is to be understood as meaning the mutually enhancing activity of two or more substances. In the present case, the combined application of two fungicides allows the application rate of the fungicides to be reduced while still maintaining an equally good fungicidal activity, or that identical application rates of the fungicides result in a greater activity than the activity to be expected from the individually employed active substances.
The utilization of such synergistic effects allow the application rates of the components to be considerably reduced, and it is possible to control a broad range of wood-destroying fungi. The reduced application rates relate to the quaternary ammonium salts, but also to cyproconazole.
In the present case, cyproconazole is combined with compounds which considerably enhance the activity of the fungicide, which allows the identical activity to be obtained by using a lower concentration of the fungicide. In addition, the combinations according to the invention are active even when used at low application rates. They are therefore outstandingly suitable for controlling wood fungi in wood and masonry.
The present invention therefore relates to fungicidal compositions which comprise
A) cyproconazole (Formula I) 
xe2x80x83in combination with
B) inorganic or organic ammonium salts of the formula II 
xe2x80x83in which R1-R4 are identical or different and are an organic substituent which has up to 18 carbon atoms and which is bonded by a carbon-nitrogen bond, or three of the radicals R1-R4 together with the nitrogen atom form a heteroaromatic system, for example pyridinium, xnxe2x88x92 is the anion of an inorganic or organic n-basic acid, and n is 1, 2 or 3.
The compounds of type B are preferably ammonium salts in which R1-R4 are identical or different and are (C1-C18)-alkyl, (C7-C13)-aralkyl, such as benzyl, (C1-C6)-alkyoxy-(C1-C12)-alkyl, [xe2x80x94CH2xe2x80x94CH2xe2x80x94O]xxe2x80x94H or [xe2x80x94CH(CH3)xe2x80x94CH2xe2x80x94O]xxe2x80x94H and x is 1, 2 or 3. Particularly preferred salts are those in which R1 and R2 are in each case (C1-C4)-alkyl, in particular methyl, R3 and R4 are in each case (C8-C12)-alkyl, in particular decyl. Preferred anions Xnxe2x88x92 are Clxe2x88x92, Brxe2x88x92, SO42xe2x88x92, HSO4xe2x88x92, PO43xe2x88x92, HPO42xe2x88x92, H2PO4xe2x88x92, CH3COOxe2x88x92, COO22xe2x88x92, SCNxe2x88x92, in particular Clxe2x88x92.
Most of the wood-destroying fungi are Basidiomycetes, but Ascomycetes and Deuteromycetes can also be found. The compositions according to the invention are preferably used against Basidiomycetes, for example against Coniophora, Gloephyllum, Poria, Serpula and Coriolus. The following fields of application are of particular interest: preventive and curative treatment of wood, and curative treatment of wood and masonry.
The compounds of type B can be combined with cyproconazole to give a range of combinations. Cyproconazole and quaternary ammonium salts are commercially available.
The mixing ratios of the individual components in the combinations according to the invention can vary within wide limits. However, quantitative ratios of between 2:5 and 1:25, preferably between 1:4 and 1:6, are selected for practical reasons.
The mixtures according to the invention can be in the form of water-dilutable concentrations which are then applied in a customary manner in the form of a dilution with water, or in the form of so-called tank mixes which are prepared by concomitant dilution of the separately formulated components with water immediately prior to application. They can also be applied in the form of aqueous ready-for-use solutions.
The application rates of the fungicides of type A in the active substance mixtures are generally between 1 g/l and 100 g/l, the application rates of B are between 5 g/l and 500 g/l; the total amount of product combination to be applied is 15 l/m3 to 600 l/m3 of wood.
The compositions according to the invention can be marketed in the form of the conventional preparations which are known to a person skilled in the art. They are preferably marketed in the form of water-dilutable concentrates or ready-for-use solutions. The formulated compositions contain for example 0.1 to 50% by weight of the active substance combinations according to the invention.
Examples of inert substances which can be used are n-butyl glycolate, polyglycol ether or dipropylene glycol monoethyl ether.
In the case of fungicidal compositions, the concentrations of the active substances in the commercially available formulations can vary. The active substance concentration in emulsifiable concentrates is approx. 1 to 50%.
If appropriate, the commercial concentrates are diluted in the customary manner for application. The application rate and the concentration required varies depending on the field of application, for example for the treatment of wood without or with contact with the soil or water.
A combination of the active substances means that the fungicidal active substances are applied jointly or a few days one after the other, in the form of a so-called split application.
If required, the compositions according to the invention can be combined with other active substances, preferably with fungicides and insecticides. Unless otherwise indicated, percentages are percent by weight. The invention is illustrated by the example which follows without limiting it thereto: